This institution is continuing to gather data from patients entered in the various NSABP protocols. We have made a major contribution to Protocol #4 which is designed to evaluate the relative efficacy of radical mastectomy and total mastectomy with radiation and total mastectomy alone in patients with clinically negative axillary nodes, and to compare radical mastectomy with total mastectomy and radiation in patients with positive axillary nodes. In addition, we are maintaining close follow-up of patients entered in the following: (1) Protocol #7 which compares the effect of postoperative L-PAM plus 5-FU with L-PAm alone in patients with histologically positive axillary lymph nodes; (2) Protocol #8 - designed to compare L-PAM, 5-FU, and Methotrexate with L-PAM plus 5-FU in patients with positive axillary lymph nodes following radical mastectomy; (3) Protocol #9 which compares L-PAM plus 5-FU plus Tamoxifen with surgery with L-PAM plus 5-FU with surgery, and is designed to determine whether Tamoxifen in combination with L-PAM and 5-FU is more effective in patients whose tumors have positive estrogen receptor sites; and (4) Protocol #6 - evaluation of segmental mastectomy with and without radiation. We will implement Protocols R-01 and C-01 for colo-rectal carcinoma as soon as they are open for patient entry, and the Stage III breast protocol when it becomes finalized and open for patient accrual. In summary, the overall objectives of this project remain the same: (a) to evaluate the efficacy of presently employed modalities such as surgery and radiation therapy in the treatment of operable primary breast cancer; (b) to estimate the worth of new and promising combined adjuvant therapeutic modalities prior to their general use; (c) to gather biologic and other pertinent data from patients with such tumors; (d) to evaluate the effects of therapy on the response of the hosts; and (e) to dedicate our efforts to seeking newer and more effective cancer treatment through multimodality therapeutic regimens and participating in the deliberation, planning, and design of new protocols.